    <script type="text/javascript" src="http://www.google.com/jsapi"></script>
    <script type="text/javascript">
      google.load("visualization", "1", {packages:["corechart"]});
      google.setOnLoadCallback(drawChart);
      function drawChart() {
        var data = new google.visualization.DataTable();
        data.addColumn('string', 'time');
        <% @chart_keys.each do |key| %>
	   <%= "data.addColumn('number', '#{key}');" %>
	<% end %>

        data.addRows([
	<% @chart_data.each do |point| %>
	   <%= point %>
        <% end %>

        ]);

        var chart = new google.visualization.AreaChart(document.getElementById('content'));
        chart.draw(data, {legend: 'none', pointSize: 1, width: 1200, height: 900, title: 'Power Data', 
                          hAxis: {title: ' ', titleColor:'#FF0000'},
                         });}
    </script>

<DIV id="content" style="position:absolute; top:10px; left:75px;" width="1200" height="900"></DIV>
